Electric regulator.



UNITED STATES PATENT` OFFICE.

LOUIS WILLAIRD THOMPSON, OF NEW YORK, N. Y., ASSIGNOR TO GENERAL ELECTRIC f COMPANY, A CORIORATION OF NEW YORK.

Ennesimo nusuna'ron.

Specification of letters Patent.

'Patented Dec. 19, 1916.

To all 107mm t may concern.'

Be it known that I, Louis VW'ILLARD THOMPSON, a. citizen of the United States, anda resident of the borough of Manhattan, city, county, and State of New York, have invented certain new and useful Improvements in an Electric Regulator, of which the following is a description, accompanied by drawings.

This inventionlrelates to electric regulators, but more particularly to alternating current voltage regulators, for automatically maintaining thevoltage of a generator by effecting momentary changes in the .field of the generator, such changes being greater than those which would be required to restore the desired voltage if the changed condition in the field of the generator were conbe substantially free from hunting tinuously maintained.

In voltage regulators of this character, in which the momentary changes in the field of the generator' are effected in response to ythe generator-voltage, the electrical and me- 'chanical inertia of (the parts produces a fluctuation inthe generator voltage much greater than the small fluctuation necessary to the operation of the field `,changing means. This condition, commonly known hunting, is highly objectionable.

The primary object of this invention is, therefore, to provide a regulator which shall this end means, to the operation of which fluctuations in the generator voltage are not essential, are employed toimpart to the controlling member oi the field changing means a vibratory movement. The means to produce this vibratory movement comprise `an oscillatory circuit, including a condenser andthefwgindingfof the regulator, which is responsive to the generator voltage, or an 'independent winding adapted to act cumuvlatively with said regulator Winding.

To modify the vibratory movement and prolong its duration a resiliently supported weight is attached to the field changing means.

Obviously other oscillatory circuits and l connections may be devised without departing from the spirit of the invention, and I am not to be understood as limiting the in- .'vention to ,the apparatus shown and dematic representation of circuits and apparatus for carrying out the invention, and Fig. 2 is a similar representation`of a modiiicatien.

Referring to the drawings, A represents an alternating current generator connected to the mains B, C, the voltage upon which is to be regulated. The field C of the alternator is excited by a direct current exciter I) and the voltage of the mains B, C is regulated by regulating the excitation. The voltage ofthe exciter I) is Varied, by varying the strength of its field E, in the circuit of" which is shown an exciter rheostat F. This rheostat F, as shown, may be short circuited by means of the contacts G and Il controlled by suitable means.

In the drawings, I have illustrated tivo modifications of suitable electro-responsive means for controlling the alternate opening and closing oit contacts G-H.

Vith particular reference to Fig. l. a solenoid .I is connected across the mains B--C, by means of the leads K and L, in one of which a non-inductive resistance R is preferably inserted as usual. A magnetic core (l is suspended from one end of the lever I), which is pii'otally supported at Q and carries the contact Gr at the-other end. Contact (l is adapted to cooperate with the stationary contact Il to control the field of the exciter, and these contacts are preferably made of carbon to avoid the usual objections to metal contacts. A conductor Y extends between the point c on the solenoid .I and the contact Il. A conductor S connects one side oi' the exciter rheostat F with the contact H, while the contact G is in electrical connection with the other side of the` is preferably shunted around the contacts GQ and I-I to prevent sparking. I

For a purpose hereinafter described, a condenser X isy connected between the point a. on the solenoid J and the point b on the flexible conductor V and a weight Z1 is supported from the lever P by means of the resilient connection Z.

In the modification shown in Fig. 2, the core O is acted upon by a second coil J1,

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.from the condenser X1.

die L ,mi

1, let us assume that the voltage across themains B-C drops slightly below 'the desired value. The strength of solenoid J will correspondingly be lowered with the result that 4 the contact G is moved into engagement with the contact il, whereupon the rheostat F will be short circuited. Prior to the engagement of the conta-cts G and H, however, 'the condenser X was connected aerossthe rlicostat F and hence a charge was stored therein. Upon the engagement ofthe contactsG-llV an oscillatory discharge of the condenser X will occur through a local circuit comprising the solenoid J, conductor Y,

contact H, contact G, lever l), flexible conductor V and the condenser X, which discharge will momentarily augment the eitect upon the core t) ot' the solenoid J and cause the. contacts G and H to be disengaged.A

Upon the disengagement of the contacts G and il it is probable that the charging current to the condenser lil again augmente the cite/ct of the solenoid ,l upon the core, the effect of which would be to momentarily apply atorce in a direction to increase the opening movement of Contact G. After the disengagement ot the contacts Gl' and H, the eitect of the solenoid J upon the core Q returns to normal and the contacts tij and H will be reingaged, whereupon the cycle ot movement will be repeated. The resiliently supported weight Z improves the action or the regulator in that it modilies the responsiveness of the contact carrying lever P to the momentary changes in the solenoid J and hence modifies the amplitude and duration of the vibratory movement of said lever. ll`he condenser ill, as previously mentioned. prevents excessive sparking at the contacts G and H.

rlhe operation of the modification shown in Fig. 2 is substantially the same as the operation of the modilication shown'in Fig. l, the only difference being that in Fig. 2 a separate coil J1 which cooperates with the coil J, receives the oscillatory discharges It' the voltage ol the Generator has the desired value the i: i

mean position ot the lever l will be such that iirits vibrations the relative periods during which the contacts (il and ll are eno u n gaged o'r disengaged will be such that substantially no change in the voltage of the eine, the

. such l that in its vibration the relaaye periods A during which the contacts G ano gaged or disengaged will he such voltage o1" the generator v ll. be iii Similarly, it the voltage of the Y rises above the desired value, the mean posi tion of the lever P will be such in its vibration the relative periods during which the contacts G and H are engaged or disengaged will be such that the voltage oit the generator will loe decreased.

it is, ot' course, obvious that it the rolt` age ot the generator increases or decreases by a sultciently large increment, the vi tion of the lever P, due to the oscillatory circuit, will cease until the voltage of the generator again approaches the desired yalue` l claim and desire to obtain by Letters .Patent the following:

l. ril`lie combination with an alternati current circuit to be regulated, of a reg tor comprising electro-responsive means, responsive to a departure from a desired condition, for restoring said desired condition, and means comprising a condenser Por iniare enpressing an oscillatory current upon said electro-responsive mea-ns.

2. The combination with an current circuit to be regulated, ci" a tor comprising electro-responsive i sponsive to a departure from a dition for restoring said desired ai an oscillatory circuit controlled by the reguv linac lator and including said electro-respoiisive means for impressing an oscillatory current upon said electro-responsive means.

3. rlhe combination with an alternating currrent circuit to be regulated, of a' regulator comprising electro-resljionsive means, re sponsive to a departure from a desired condition, land an oscillatory circuit controlled by the' regulator tor modifying the restoring action of said regulator.

il. rl`he combination with an alternating `current circuit to be regulated, oi a regula tor comprising an electro-reslionsive device and an oscillatory circuit adapted to be closed by said regulator, for in tlueiicing and modifying the action ot said electrosresponsive device.

current generator and its circuit to be regulated, of an electro-inagnet responsive to the voltage. in said circuit, contacts controlled by said magnet ior regulating the Voltage ot the generator, and a condenser sliunting the magnet and controlled by said contacts.

(i. The combination with an alternating current generator and its circuit to be regurestoring said desired condition,

Cil

.lili

o. ihe con'ibination with an alternating:

lated, of an electro-magnet responsive to the voltage in said circuit, contacts controlled by said magnet for regulating the voltage of the generator, and a condenser brought into operation by the closing of said contacts for influencing and modifying the action of said electro -ma guet.

7. The combir tion with an alternating current generator and its circuit to be regulated, of an electro-magnet responsive to the Voltage in said circuit, contacts controlled by said magnet for regulating the voltage of the generator, and a condenser included. in the-circuit of the electro-magnet and connected to be discharged by the closing of said contacts.

8. The combination with an alternating current generator and its circuit to be regulated, of an electro-magnet responsive to the voltage in said circuit, contacts controlled by said magnet for regulating the voltage of the generator, and an oscillatory circuit, in`- cluding the electro-magnet, and connected to be closed by said contacts.

9. In a regulator, the combination ot an electro-responsive device, means for impressing alternating current voltage upon said device, means for sui'ierimposing oscillatory current upon said device, and regulating means controlled by said device.

10. The combination with an alternating current circuit to be regulated, of a regulater comprising a controlling magnet, and a condenser connected to be discharged by said magnet for altering the restoring power of said magnet.

1l. The combination with an alternating current circuit to be regulated, of a regulator responsive to electrical conditions in said circuit, and a condenser for altering the responsiveness ot said regulator to said conditions after it' has been set in operation by said conditions.

12. The combination with an alternating current generator having a lield, ot a resistance affecting the strength of said field, contacts opening and closing to insert and withdraw said resistance, means responsive to variations otl voltage of said generator from a desired value for opening and closing said contacts, said resistance being greater than that which would be required to etlect the required change in voltage it continuously applied, and a condenser acting on said contact opening and closing means for n'ioditfying the operation thereof.

13. In a system ot' regulation for an alternating current generator, the combination otl a generator, an exciter therefor, a resistance Jfor the exciter field, a switch adapted to control the insertion and removal of said resistance, a lever carrying a movable contact oi said switch, a 'mass resiliently supmagnet adapted either to be short circuited or to be placed in shunt to said resistanceby the movement of said lever.

Il. The combination with an alternating current generator of a regulator compri-sing a switch, a member carrying the movable element of said switch, an electromagnet responsive to an electrical condition ot' said generator for actuating said element, a mass r'esiliently supported on said member, a circuit including a winding of said electromagnet and means controlled by said switch tor energizing said winding.

15. The combination with an alternating current generator ot' a regulator comprising an electromagnet responsive to an electrical condition ot' said generator, means operated by said electromagnet for regulating the electrical condition of said generator', a resiliently supported weight coperating with said means to modify the action thereof, a circuit including a winding ot' said 'electromagnet, and means controlled by the firstnamed means for energizing said winding.

1G. In a regulator the combination of a switch having a movable contact, means comprising a member to which is operatively connected a core. and on which is resiliently mounted a mass for operating said contact, a solenoid arranged to operate said core and an oscillatory cire-uit controlled by said switch to modify .the effect ot' said solenoid upon said core.

17. In a regulator the combination of a switch having a movable contact, means comprising af member to which is operatively connected a core for operating said contact, a solenoid arranged to operate said core and means comprising an oscillatory circuit, controlled by said switch and acting upon Said core, and a mass, resiliently supported by said member, to impart a vibratory movement to said contact.

18. In a ysystem o't' regulation for an alternating current generator, the combination with the generator of a regulator comprising an electromagnet responsive to the generator voltage, a switch-operated by said electromagnet for controlling the generator voltage, and an oscillatory circuit including a winding for said electromagnet and controlled by said switch.

ln testimony whereof I have signed this specification in the presence of two subscribing witnesses.

LOUIS WILLARD THOMPSON.

l/Vi tnesses z WALTER S. JONES, HERBERT G. OGDEN. 

